I had posted a ticket and was asked by the GM to post this here so that others would be aware.
There is a known issue with the battle.net desktop app with the friends list (favorites and notes) which is also affecting the friends lists in games.
This is the ticket:
I cannot remove anyone from favorites from my friends list in game. I also cannot add, change, or remove any notes from my friends list in game.
I made sure to close all programs and end all blizzard/battle.net processes. Then I completely uninstalled battle.net and World of Warcraft. Then I deleted all folders from %APPDATA%, %LOCAL%, %PROGRAMDATA%, and %TRMP%. I also uninstalled twitch and Overwolf/Curse Forge.
Then I rebooted and made sure that they were all still gone/uninstalled/deleted.
Then I did a fresh install of Battle.net and or World of Warcraft. No addons or anything. It still did not work. I still could not add or remove friends from favorites, or add, change, or remove notes from friends.
I then made a new admin account on my computer, did a fresh install of battle.net and World of Warcraft, and ran them as an administrator. Still no fix.
Is it possible that there is an issue with my battle.net or account data on blizzard’s side?
Your ticket has received the following response:
Game Master Ixzal here and sorry to hear about this situation with removing favorites. We have received similar reports and based on everything you have tried, this seems like a bug with the Blizzard app. We can forward this issue to the Bug team but I would also recommend reporting this issue on the forums:
In the mean time, you may want to try testing another computer to see if there’s any change.